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Tom-D

Tom-D

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Tom-D
Post Maintenance Check Flights, IAW 91,407 (b)

(b) No person may carry any person (other than crewmembers) in an aircraft that has been maintained, rebuilt, or altered in a manner that may have appreciably changed its flight characteristics or substantially affected its operation in flight until an appropriately rated pilot with at least a private pilot certificate flies the aircraft, makes an operational check of the maintenance performed or alteration made, and logs the flight in the aircraft records.

Heres the question.

You have been assigned the task of testing an aircraft that has 3 new STCs installed, 4 field approvals, an upgraded engine, which has been rebuild but not flown yet, A different prop that is not on the type certificate, every thing on the aircraft has been off cleaned and replaced, including the wings and all the flight controls, and completely re-wired.

How do you approach the task?
 
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Prop not on the type? Isn't that grounding right there?

Anyway, there's my answer. I would go through all of it looking for a reason not to fly it. Every single thing would have to be proved to be airworthy before I got in. The bias is towards 'not safe/not legal' until proven otherwise on each affected system.
 
Carefully, and with a lot of planning and forethought. That's how.

Or are you asking for an internet version of Experimental Test Pilot School?
 
Tom-D said:
Post Maintenance Check Flights, IAW 91,407 (b)

(b) No person may carry any person (other than crewmembers) in an aircraft that has been maintained, rebuilt, or altered in a manner that may have appreciably changed its flight characteristics or substantially affected its operation in flight until an appropriately rated pilot with at least a private pilot certificate flies the aircraft, makes an operational check of the maintenance performed or alteration made, and logs the flight in the aircraft records.

Heres the question.

You have been assigned the task of testing an aircraft that has 3 new STCs installed, 4 field approvals, an upgraded engine, which has been rebuild but not flown yet, A different prop that is not on the type certificate, every thing on the aircraft has been off cleaned and replaced, including the wings and all the flight controls, and completely re-wired.

How do you approach the task?
Click to expand...

If the paper work is in order, first I would dynamically balance the prop and get readings throughout the power band. If everything checks there I take off and do a flight regime check and develop the new performance tables.
 
Ron Levy said:
Carefully, and with a lot of planning and forethought. That's how.

Or are you asking for an internet version of Experimental Test Pilot School?
Click to expand...

Nope, just seeking the opinions of the group.
 
Captain said:
Prop not on the type? Isn't that grounding right there?
Click to expand...
Not always many times the prop used will be in the STC that upgraded the engine.
Captain said:
Anyway, there's my answer. I would go through all of it looking for a reason not to fly it. Every single thing would have to be proved to be airworthy before I got in. The bias is towards 'not safe/not legal' until proven otherwise on each affected system.
Click to expand...

How would you know if the proof of airworthiness is correct ?
 
Henning said:
If the paper work is in order, first I would dynamically balance the prop and get readings throughout the power band. If everything checks there I take off and do a flight regime check and develop the new performance tables.
Click to expand...

Why would you go thru all that if the prop was approved by other means?
 
Tom-D said:
Why would you go thru all that if the prop was approved by other means?
Click to expand...

Because dynamically balancing the prop is the best value in aviation, and just because the type of prop is approved does not mean that particular prop is perfect. I have never seen a plane that did not benefit from the process.
 
Henning said:
Because dynamically balancing the prop is the best value in aviation, and just because the type of prop is approved does not mean that particular prop is perfect. I have never seen a plane that did not benefit from the process.
Click to expand...

You would require this prior to the test flight?
 
Tom-D said:
You would require this prior to the test flight?
Click to expand...

Sure, I wouldn't require it to fly your plane, I'd require it if it was mine because it would show me that everything was in go shape and not going to tear stuff up that was going to cost me money. If you want me to test your plane and don't want to do it, that's fine by me, I'll go fly and do the rest.
 
very very very carefully.....
 
Simple. For instance, every jet we install an new antenna on via other than an STC goes on a test flight to cover 91.407, looking for any unusual vibration or buzzing sounds. We provide them a checklist of maneuvers, which is pretty much every normal maneuver during any other flight, and the crew signs a log entry saying nothing unusual was noticed on test flight per 91.407.


It speaks volumes that it seems like this is the first time you've ever seen this rule.
 
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Ron Levy said:
Well, then you have mine.

Carefully, and with a lot of planning and forethought. That's how.
Click to expand...

And that is pretty much mine too, and I would add, a lot of trust in who did the work.
 
bnt83 said:
It speaks volumes that it seems like this is the first time you've ever seen this rule.
Click to expand...

I hope the you've doesn't refer to me? I simply posted it as a reference. so you would't have to go look it up.
 
I'm sure that process has been followed with every new aircraft design. Whatever it may be.
 
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